Automotive Air Conditioning Information Forum (Archives)

edp on Tue April 26, 2011 1:29 PM

Hi all, been poking around here on & off for a while, heres what I've got going....

1973 Datsun 1200 project - never had AC but will now. I bought a few components & am trying to figure out what my next steps need to be.

Here's the pieces - Hitachi MJ167-4PD, new OEM NOS for datsun/Nissan 310's & 280Z cars I think, maybe a few other models...



the condensor - a American Condenser P40225P aux condenser for Caravan/Voyager rear AC setup's - really small to fit behind core support of car


Hot rod Components Model 7072 underdash Evap unit w/blower - is that an expansion valve on the side of the unit? (probably a dumb question...)



heres where the condenser will fi - blue tape on core support...


fittings I took off a 280Z, late 70's I think in the wrecking yard, they look exact to the compressor & I was planning on taking them to a hose & tube guy to have him cut & weld new compression ends onto them & then make the hoses..



so thats what I've got, I need to get the dash installed so i can fit the evap unit then the hose routing can be figured out.

Some other questions I have are:
Is the compressor oil or refrigerant specific, if so - which ones do I use?

How do I figure out which fittings for the condenser?

Which port on the compressor & the condenser go to where to figure out the hose routing?

What type / kind of dryer do I need?

Is the condenser too small & will it need its own fan / 's ?

I'm sure there's other questions I should ask just not sure which - I need an AC guru to come over & help me figure this out, anyone in seattle ?

BTW - here's a computer case fan that fits the condenser perfectly, in fact it'll take two if need be, I can buy these in 12V & was thinking this might be an option for cooling the condenser if need be, what do you guys think?


Enough for now, thanks for any help you guys can provide!

Evan



Edited: Tue April 26, 2011 at 1:34 PM by edp

TRB on Tue April 26, 2011 4:27 PM

To little condenser and those fans will never move enough air to dissipate the heat load.

-------------------------

When considering your next auto A/C purchase, please consider the site that supports you: ACkits.com
Contact: ACKits.com

edp on Tue April 26, 2011 8:36 PM

what if I ran 2 in series, can that be done & work?

mk378 on Tue April 26, 2011 8:53 PM

Look at a '95 Civic condenser, it is about the same shape as your radiator. You may need to modify the lines on the side though. Can the radiator be moved back to make room for the condenser?

TRB on Tue April 26, 2011 9:12 PM

Quote
Originally posted by: edp
what if I ran 2 in series, can that be done & work?

A CPU fan moves about 90 CFM. The 9 inch Maradyne will move 800 CFM.

-------------------------
When considering your next auto A/C purchase, please consider the site that supports you: ACkits.com
Contact: ACKits.com

chris142 on Tue April 26, 2011 10:52 PM

I don't think that compressor will like R134a.

Don't use Compression fittings.

Condensor too small.

Fans wont do it.

The secret to a good working AC is heat removal from the system.The condensor removes the heat. It needs lots of air and surface area to do it's job. That condensor looks more like a trans cooler.

TRB on Tue April 26, 2011 11:01 PM

Quote
Originally posted by: chris142
I don't think that compressor will like R134a.



Don't use Compression fittings.



Condensor too small.



Fans wont do it.



The secret to a good working AC is heat removal from the system.The condensor removes the heat. It needs lots of air and surface area to do it's job. That condensor looks more like a trans cooler.

+1

Also should note. That condenser is a pre cooler condenser for dual unit caravans. They also have a main condenser on these vehicles.



-------------------------
When considering your next auto A/C purchase, please consider the site that supports you: ACkits.com
Contact: ACKits.com

edp on Wed April 27, 2011 1:03 AM

I realize the condenser is small as well as it being the rear air aux condenser for the caravan, it was actually suggested by someone here a few months back because of its size & the limited space I have to work with, thats why I have it, it'll fit the space behind the core support - if someones got a better idea of where to fit a condenser I'm all ears.

What I meant by running two was two condensers in series essentially doubling the condenser size - is that possible to do successfully? I was also thinking of 2 fans, the fan I showed was just an example of the size - cpu fans come in all kinds of CFM ratings & I'd look for the highest possible output if I was going to go that route. I was talking to a Spal fan dealer about small fans & there might be something available from them that has much higher output.

there are all kinds of 10" x 16" condensers but they wont fit, I cant move the radiator w/o altering the core support, the radiator is a stock one re-cored to a 3 tube core instead of 2. I realize this is a challenge & not everything is ideal, what I want to know is what will it take to make it work properly within my existing parameters.

Thanks, Evan

Edited: Wed April 27, 2011 at 1:28 AM by edp

edp on Wed April 27, 2011 1:30 AM

Quote
Originally posted by: chris142
I don't think that compressor will like R134a.



Don't use Compression fittings.



Condensor too small.



Fans wont do it.



The secret to a good working AC is heat removal from the system.The condensor removes the heat. It needs lots of air and surface area to do it's job. That condensor looks more like a trans cooler.


So whats wrong with the fittings & what should I use?

So is R12 the answer for the compressor then?

bohica2xo on Wed April 27, 2011 2:53 AM

That condensor is the right height, but about half the length of the aftermarket stuff I recall. Those units ran across both of the square cutouts in the radiator support - sort of "ear to ear" across the support behind the grille.

A pair of the condensors in your pic, plumbed in series would be better than one. Keeping in mind everything you are doing is a compromise of one kind or another. Be sure to install an HPCO in this system, chances are it will be very necessary while you work out the airflow & condensor bugs.

The peanut fitting that is on that condensor is available - Tim should have them. The two bolt flanges in your pics take standard fittings - Tim has those as well. You can buy a crimp tool, fittings & bulk hose from Tim @ AC Kits, or have the hoses made up by fitting all the parts & having a local hose outfit crimp the connections for you.

HERE is the original thread on this project

B.

-------------------------
"Among the many misdeeds of the British rule in India, history will look upon the act of depriving a whole nation of arms, as the blackest."
~ Mahatma Gandhi, Gandhi, An Autobiography, M. K. Gandhi, page 446.

chris142 on Wed April 27, 2011 11:07 PM

Quote
Originally posted by: edp
Quote
Originally posted by: chris142
I don't think that compressor will like R134a.







Don't use Compression fittings.







Condensor too small.







Fans wont do it.







The secret to a good working AC is heat removal from the system.The condensor removes the heat. It needs lots of air and surface area to do it's job. That condensor looks more like a trans cooler.





So whats wrong with the fittings & what should I use?



So is R12 the answer for the compressor then?

You want a shop or the site sponsor to weld barbed fittings onto your exising fittings so that you can slide a hose over the barb and crimp it like OE.

The choice or refrigerant is up to you but here R12 is crazy expensive. Were not doing R12 at my shop this year unless we find some cheap.

edp on Thu April 28, 2011 12:24 PM

Thanks Chris & Bohica,

Chris, the method or fitting repair is what I was thinking of, I found a guy in my area to do the hoses & fittings, he's a hydraulic shop & has the AC press setup - he was recommended form Doc's Blocks - seems like that method will work well & thats what the local guy recommended as well.

Bohica - I looked into the longer versions of the condensers that are available in the same basic height dimensions as the smaller one I've got, problem was when I mocked up one out of wood to the same dimensions it hit the backside of the grill so it was a no go. If the real one had slightly different tab dimensions I might be able to make it work, w/o having it on hand I just dont know that why I went with the smaller one. I understand I'm trying to force a solution & it'll never be ideal but my hope is to make it work.




If I stacked 2 of the P40225P's condensers a top one another in the core support hole I might able to get a 6" to 8" low profile Spal fan behind - like this...
http://www.the-fan-man.com/shop/size-push-part-0393-p-180.html?cPath=33

If I did stack the 2 condensers which ports connect to one another to make if flow in series?

Thanks for all the help, I realize my method is a bit unconventional & I appreciate the input!

Evan

BTW - how'd you find the original thread? I tried searching user names & didn't get anywhere.

bohica2xo on Sat April 30, 2011 7:21 PM

On the issue of grille interference, you need to step back to 1973...

That car was a cheap jap-can, with no A/C. If the grille was an 1/8th of an inch from going back into place the grille would have had a visit to the disc grinder or belt sander. The owner would have never known, and likely would not have cared either. The condensor I recall may well have required a small modification to the grille. The mechanic was probably more worried about that sewing machine under the hood having enough power to run the compressor at idle...

If you use two units in series, you would feed gas into the top of the first one, and whatever was leaving the bottom of the first one would be fed to the top of the second one. You would plumb the bottom port on the second condensor to the receiver, and from there to the TXV.

Search? I just use the advanced site search. Most people hate it, but it is still there.

B.

-------------------------
"Among the many misdeeds of the British rule in India, history will look upon the act of depriving a whole nation of arms, as the blackest."
~ Mahatma Gandhi, Gandhi, An Autobiography, M. K. Gandhi, page 446.

NickD on Sun May 01, 2011 1:50 PM

When the Japanese wanted to enter the USA car market, they called their old ASIX buddies the Germans for advice and what to name their new car. Germans, since they were in the US car market asked them when did they want this information. Japanese replied immediately, Germans replied dat soon?

Anyway, this is how your car got it name.

Just thought I would lighten up things a bit, how did you find that car in such good condition, up north here, were a pile of rust before the first year ended.

edp on Sat May 07, 2011 1:44 PM

Bohica,
the grill idea isn't a bad one, problem is I only have unbroken ones in good condition & am not interested in molesting them into a modified version. I will look for another one & think about going that route. I know the other caravan condenser is almost double the size so i assume that'll be quite helpful.

I did manage to get the OEM compressor fittings disconnected from the hoses after a good soaking of penetrating oil, their the flare fitting type ( think flare style on a brake line if I'm using the wrong terminology) on the hose end attaching to the threaded block portion attached to the compressor. I assume i can have new hose connections welded / brazed to these & start the new hoses from there.

Nick, I wish I'd found the car in this good a condition, its only that way cuz i spent gobs of time doing it, all part of the fun! thanks for the compliment.

Evan

Here's the compressor fittings off the 280Z, the plan would be to cut these off at the compression end & weld/braze whatever type fitting I need to start the line from there - is that how its done? Also, will I need a separate low pressure switch or is that something that will come as part of the accumulator / dryer?



Edited: Sun May 08, 2011 at 3:22 PM by edp

bohica2xo on Sun May 08, 2011 5:47 PM

Evan:

I understand your reluctance to modify an original grille. Since it has been three decades since that item was available off the shelf, I would not want to either. I was just describing how it was probably done as an aftermarket install when the car was nearly new.

How much does the grille interfere with the bigger condensor? Would it be possible to put hollow standoffs over the mounting screws, and space it forward say .250 & make it fit?

Perhaps a custom grille for the A/C & stash the OEM grille?

B.

-------------------------
"Among the many misdeeds of the British rule in India, history will look upon the act of depriving a whole nation of arms, as the blackest."
~ Mahatma Gandhi, Gandhi, An Autobiography, M. K. Gandhi, page 446.

fasto on Sat June 11, 2011 2:40 PM

I know it's an old thread...
I've got the same compressor in my 280Z (factory or dealer air, can't tell which). It's a neat unit, it has a gerotor oil pump built in even though the oil also circulates with the refrigerant.
I converted the 280Z to R134a last spring to see if it would work. I used ester oil and the R12 charge weight less 5%. The A/C in the car works just fabulously, even though the cooled air can only be directed out the center vents - a poor system design not helped by the black vinyl interior. So far the compressor is working with no trouble. The 280Z air conditioner even with the R134a refrigerant is vastly better than my VW Corrado A/C, probably because of the 170 HP condenser fan in the 280Z (btw those little computer fans aren't going to work at all, the electric fan in the VW draws 45-50A which is around 3/4 HP and is completely inadequate). I'd have no hesitation in using that compressor with R134a given enough condenser area and airflow.